An opera singer in a convertible sings a note at 700 Hz while cruising down the highway at 90 km/h . The speed of sound in the air is 343 m/s. 1. What is the frequency heard by a person standing beside the road in front of the car?
2. What is the frequency heard by a person standing beside the road behind the car?

i think it’s a. this is because if they measured the mass of something with a mass of 150g, then their final answer would have to be approximately 150g. though all of their answers are almost 150, rosa and tran have the closest answers (or the exact answer) to the accurate one.

a straight line sloped

the skeletons of most mammals reach a certain size and then stop growing. however, many animals, including some mammals, keep growing throughout their lives. kangaroos, for example, just keep growing and growing until they die. also, the longer an animal lives the greater the chance it might catch some deadly disease.